ICSEClass XPhysicsCurrent Electricity03 Mark2023 Easy

QQuestion

(a) Define specific resistance.

(b) What happens to the specific resistance of a conductor if its length is doubled?

(c) Name a substance whose specific resistance remains almost unchanged with the increase in its temperature.

Exam-ready answer 03 Mark

Answer

(a) Specific resistance is the resistance of a wire of that material having unit length and unit area of cross-section.

(b) It remains unchanged because specific resistance is independent of the dimensions of the conductor.

(c) Manganin.

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